The present invention generally deals with testing transceivers. Conventional systems for testing transceivers will now be discussed with reference to FIGS. 1-2E.
FIG. 1 illustrates a conventional system 100 for testing a transceiver 104.
As illustrated in the figure, system 100 includes a signal generator 102, transceiver 104 and a signal tester 106. Transceiver 104 includes a receiver 108 and a transmitter 110. System 100 additionally includes communication channels 112, 114, 116, 118 and 120.
Signal generator 102 is in communication with receiver 108 by way of communication channel 112. Further, signal generator 102 is in communication with signal tester 106 by way of communication channel 120. Signal tester 106 is in communication with receiver 108 by way of communication channel 114. Further, signal tester 106 is in communication with transmitter 110 by way of communication channels 116 and 118.
Signal generator 102 may be any system or device that is able to generate a known signal to be transmitted by a receiver to test the transceiver.
Transceiver 104 may be any system or device that is able to transmit a signal and receive a signal. In cases wherein the transmitted signal is the received signal, transceiver is a repeater.
Signal tester 106 may be any system or device that is able to receive to known signal and determine if the received signal is correct and within a certain threshold of a predetermined acceptable signal.
Receiver 108 may be any system or device part of a transceiver that is able to receive or accept a signal.
Transmitter 110 may be any system or device part of the transceiver that is able to transmit a signal.
Transceiver 104 is tested with signal generator 102 and signal tester 106. Receiver 108 and transmitter 110 are tested separately.
To test receiver 108, signal generator 102 provides known test signal 122 to receiver 108 by way of communication channel 112.
Test signal 122 is a predetermined signal having predetermined parameters, such as amplitude, frequency and/or phase. Receiver 108 will have a predetermined transfer function. As such signal 138 that is output from receiver 108 should have a known correspondence to test signal 122. If signal 138 deviates from the known correspondence, then receiver 108 is not working properly.
Signal tester 106 determines whether receiver 108 is working properly. In particular, signal generator 102 provides signal 126 to signal tester 106. Signal 126 informs signal tester 106 of signal 122. In some cases signal 126 may be signal 122. Signal tester 106 has knowledge of the transfer function of receiver 108, such that signal tester 106 is able to determine the expected output signal from receiver 108 based on signal 122. Accordingly, signal tester 106 can compare signal 138 with the expected output signal from receiver 108 to determine whether receiver 108 is operating within acceptable parameters.
In some cases, if receiver 108 is not working within acceptable parameters, then transceiver 100 is discarded. In some cases, if receiver 108 is adjustable, signal tester 106 may provide an adjusting signal 128 to receiver 108 via communication channel 114. In this manner the operation of receiver 108 is adjusted. Receiver 108 may then be tested again, and adjusted if needed. This process continues until receiver 108 is operating within acceptable parameters or until a determination is made to discard transceiver 100.
To test transmitter 110, signal tester 106 provides a known test signal 136 to transmitter 110 by way of communication channel 132.
Test signal 136 is a signal having data that informs transmitter 110 to generate a specific signal. Transmitter 110 will have a predetermined transfer function. Signal 124 that is output from transmitter 110 should have a known correspondence to test signal 136. If signal 124 deviates from the known correspondence, then transmitter 108 is not working properly.
Signal tester 106 determines whether transmitter 110 is working properly. Signal tester 106 has knowledge of the transfer function of transmitter 110, such that signal tester 106 is able to determine the expected output signal from transmitter 110 based on signal 124. Accordingly, signal tester 106 can compare signal 124 with the expected output signal from transmitter 110 to determine whether transmitter 110 is operating within acceptable parameters.
In some cases, if transmitter 110 is not working within acceptable parameters, then transceiver 100 is discarded. In some cases, if transmitter 110 is adjustable, signal tester 106 may provide an adjusting signal 130 to transmitter 110 via communication channel 116. In this manner the operation of transmitter 110 is adjusted. Transmitter 110 may then be tested again, and adjusted if needed. This process continues until transmitter 110 is operating within acceptable parameters or until a determination is made to discard transceiver 100.
Another method of testing transceiver 100 deals with a loop hack. In a loop back test, a signal transmitted from transmitter 110 is received by receiver 108. A loop back test is much faster than the external test discussed above. However, there are inherent problems with a loop back test. For example, there is a possibility transmitter 110 is operating in an equal yet opposite improper amount than that of receiver 108 such that the overall tested loop back seems proper.
For example, suppose that transmitter 110 transmits a signal at an amplitude that is −3 dB of the required transmission amplitude and that has a phase delay of +5° of the required transmission phase. Further, suppose that receiver 108 outputs a signal at an amplitude that is +3 dB of the expected receiving amplitude and that has a phase delay of −5° of the required receiving phase. In such a case, output signal from receiver 108 would seem to accurately correspond to the input signal of transmitter 110. However, in actuality, each of receiver 108 and transmitter 110 were working improperly.
System 100 is drawn to a single receiver and a single transmitter. However, some conventional transceivers include a receiver array and a transmitter array. For example, radar array transceivers used in the automobile industry have an array of radar transmitters and an array of radar receivers. For these types of radar transceivers, all of the receivers in the receiver array and transmitters in the transmitter array have to be tested. This will be described with additional reference to FIGS. 2A-E.
FIGS. 2A-E illustrate a conventional system 200 for testing a radar transceiver 202.
As illustrated in the figures, system 200 includes signal generator 102, radar transceiver 202 and signal tester 106. Radar transceiver 202 includes a receiver array 204 and a transmitter array 206. Receiver array 204 includes receivers 208, 210, 212 and 214. Transmitter array 206 includes transmitters 216, 218 and 220. System 200 additionally includes communication channels 112, 114, 116, 118 and 120.
Radar transceiver 202 may be any system or device that is able to send and receive a plurality of signals to/from the signal generator and the signal tester.
Receiver array 204 may be any system of device that includes a plurality of m receivers, wherein m is an integer greater than 1. In this example, receiver array 204 includes four receivers.
Transmitter array 206 may be any system or device that includes a plurality of n transmitters, wherein n is an integer greater than 1. In this example, transmitter array 206 includes three transmitters. In some cases, n may be equal to m.
Radar transceiver 202 is a frequency chirp architecture, which is the most popular of the automotive CW radars. In frequency-chirped radars, the frequency of the radar signal is varied according to a pre-determined pattern. The most widely used patterns are (a) frequency-stepped, in which frequency is changed by a step in each time period and (b) Linear Frequency Modulation (LFMCW), often referred to simply as FMCW, in which transmit frequency is changed continuously within each time period. This varying frequency essentially widens the bandwidth of the radar signal, which is equivalent to narrowing the signal in the time-domain. An FMCW radar can simultaneously estimate both the velocity and range of multiple objects.
A radar beam includes a continuous series of transmitted frequency modulated “chirps”, each chirp being a short period of radar carrier transmission ramping in frequency from, for example, 77 GHz to 81 GHz. For any transmitted chirp, a plurality of reflected waves will each arrive back at radar transceiver 202 at a different time, with a different Doppler and at a different arrival angle.
An object's distance, velocity, and angle within the beam can be ascertained by analyzing the properties of their reflected waves. For chirped radar, both the velocity and distance of an object from radar transceiver 202 can be ascertained by analyzing the spectrum of the received signals. Since radar transceiver 202 has a plurality of receivers in the form of an antenna array, the angle of arrival of the reflected waves can be ascertained by analyzing the reflected wave reception across the antennas comprising the array.
To verify the accuracy of radar transceiver 202, each of receivers 208, 210, 212 and 214 in receiver array 204 and each of transmitters 216, 218 and 220 in transmitter array 206 must be calibrated or tested.
Such testing will now be described in greater detail with reference to FIGS. 2A-E. To test receiver 208, receiver 208 is tested against all transmitter within transmitter array 206. This will be described with reference to FIGS. 2A-D. For purposes of discussion, start with a test of receiver 208 using transmitter 220 of transmitter array 206. This will be described with reference to FIG. 2A.
FIG. 2A illustrates conventional system 200 for testing radar transceiver 202, wherein receiver 208 and transmitter 220 are being tested at a time t1. As such, signal generator 102 is connected to receiver 208 of receiver array 204 via communication channel 112, whereas signal tester 106 is connected to transmitter 220 of transmitter array 206 via communication channel 116 and communication channel 118. Further, signal tester 106 is connected to receiver 208 via communication channel 114. Still further, signal tester 106 is connected to all the receivers within receiver array 204 via communication channel 134. Finally, signal tester 106 is additionally connected to all the transmitters within transmitter array 206 via communication channel 132.
At time t1, to test receiver 208, signal generator 102 provides a known test signal 122 to receiver 208 by way of communication channel 112.
Test signal 122 is a predetermined signal having predetermined parameters, such as amplitude, frequency and/or phase. Receiver 208 will have a predetermined transfer function. As such, signal 138 that is output from receiver 208 should have a known correspondence to test signal 122. If signal 138 deviates from the known correspondence, then receiver 208 is not working properly.
Signal tester 106 determines whether receiver 308 is working properly. In particular, signal generator 102 provides signal 126 to signal tester 106. Signal 126 informs signal tester 106 of signal 122. In some cases, signal 126 may be signal 122. Signal tester 106 has knowledge of the transfer function of receiver 208, such that signal tester 106 is able to determine the expected output signal from receiver 208 based on signal 122. Accordingly, signal tester 106 can compare signal 138 with the expected output signal from receiver 208 to determine whether receiver 208 is operating within acceptable parameters.
In some cases, if receiver 208 is not working within acceptable parameters, then transceiver 200 is discarded. In some cases, if receiver 208 is adjustable, signal tester 106 may provide an adjusting signal 128 to receiver 208 via communication channel 114. In this manner the operation of receiver 208 is adjusted. Receiver 208 may then be tested again, and adjusted if needed. This process continues until receiver 208 is operating within acceptable parameters or until a determination is made to discard transceiver 200.
To test transmitter 220, signal tester 106 provides a known test signal 136 to transmitter 110 by way of communication channel 132.
Test signal 136 is a signal having data that informs transmitter 220 to generate a specific signal. Transmitter 220 will have a predetermined transfer function. Signal 124 that is output from transmitter 220 should have a known correspondence to test signal 136. If signal 124 deviates from the known correspondence, then transmitter 220 is not working properly.
Signal tester 106 determines whether transmitter 220 is working properly. Signal tester 106 has knowledge of the transfer function of transmitter 220, such that signal tester 106 is able to determine the expected output signal from transmitter 220 based on signal 124. Accordingly, signal tester 106 can compare signal 124 with the expected output signal from transmitter 220 to determine whether transmitter 220 is operating within acceptable parameters.
In some cases, if transmitter 220 is not working within acceptable parameters, then transceiver 200 is discarded. In some cases, if transmitter 220 is adjustable, signal tester 106 may provide an adjusting signal 130 to transmitter 220 via communication channel 116. In this manner the operation of transmitter 220 is adjusted. Transmitter 220 may then be tested again, and adjusted if needed. This process continues until transmitter 220 is operating within acceptable parameters or until a determination is made to discard transceiver 200.
After receiver 208 is tested, then receiver 210 may be tested in the same manner. This will be described in greater detail with reference to FIG. 2B. FIG. 2B illustrates conventional system 200 for testing radar transceiver 202, wherein receiver 210 and transmitter 220 are being tested at a time t2.
In operation, first of all, receiver 208 must be disconnected to communication channels 112 and 114. Then receiver 210 is connected to communication channels 112 and 114.
To test receiver 210, signal generator 102 provides a known test signal 222 to receiver 210 by way of communication channel 112.
Test signal 222 is a predetermined signal having predetermined parameters, such as amplitude, frequency and/or phase. Receiver 210 will have a predetermined transfer function. As such, signal 138 that is output from receiver 210 should have a known correspondence to test signal 222. If signal 138 deviates from the known correspondence, then receiver 210 is not working properly.
Signal tester 106 determines whether receiver 210 is working properly. In particular, signal generator 102 provides signal 126 to signal tester 106. Signal 126 informs signal tester 106 of signal 222. In some cases, signal 126 may be signal 222. Signal tester 106 has knowledge of the transfer function of receives 210, such that signal tester 106 is able to determine the expected output signal from receiver 210 based on signal 222. Accordingly, signal tester 106 can compare signal 138 with the expected output signal from receiver 210 to determine whether receiver 210 is operating within acceptable parameters.
In some cases, if receiver 210 is not working within acceptable parameters, then transceiver 200 is discarded. In some cases, if receiver 210 is adjustable, signal tester 106 may provide an adjusting signal 226 to receiver 210 via communication channel 114. In this manner the operation of receiver 210 is adjusted. Receiver 210 may then be tested again, and adjusted if needed. This process continues until receiver 210 is operating within acceptable parameters or until a determination is made to discard transceiver 200.
To test transmitter 220, signal tester 106 provides a known test signal 136 to transmitter 110 by way of communication channel 132.
Test signal 136 is a signal having data that informs transmitter 220 to generate a specific signal. Transmitter 220 will have a predetermined transfer function. Signal 224 that is output from transmitter 220 should have a known correspondence to test signal 136. If signal 224 deviates from the known correspondence, then transmitter 220 is not working properly.
Signal tester 106 determines whether transmitter 220 is working properly. Signal tester 106 has knowledge of the transfer function of transmitter 220, such that signal tester 106 is able to determine the expected output signal from transmitter 220 based on signal 224. Accordingly, signal tester 106 can compare signal 224 with the expected output signal from transmitter 220 to determine whether transmitter 220 is operating within acceptable parameters.
In some cases, if transmitter 220 is not working within acceptable parameters, then transceiver 200 is discarded. In some cases, if transmitter 220 is adjustable, signal tester 106 may provide an adjusting signal 228 to transmitter 220 via communication channel 116. In this manner the operation of transmitter 220 is adjusted. Transmitter 220 may then be tested again, and adjusted if needed. This process continues until transmitter 220 is operating within acceptable parameters or until a determination is made to discard transceiver 200.
After receiver 210 is tested, then receiver 212 may be tested in the same manner. FIG. 2C illustrates conventional system 200 for testing radar transceiver 202, wherein receiver 212 and transmitter 220 are being tested at a time t3.
In operation, first of all, receiver 210 must be disconnected to communication channels 112 and 114. Then receiver 212 is connected to communication channels 112 and 114.
The testing is similar to that discussed above with reference to FIGS. 2A-B. However, when testing receiver 212 signal tester 106 compares signal 138 with a test signal 230, wherein receiver 212 may be adjusted via adjusting signal 234. Further, when testing transmitter 220, signal tester 106 compares signal 232 with test signal 136, wherein transmitter 220 may be adjusted via adjusting signal 236.
After receiver 212 is tested, then receiver 214 may be tested in the same manner. FIG. 2D illustrates conventional system 200 for testing radar transceiver 202, wherein receiver 214 and transmitter 220 are being tested at a time t4.
In operation, first of all, receiver 212 must be disconnected to communication channels 112 and 114. Then receiver 214 is connected to communication channels 112 and 114.
The testing is similar to that discussed above with reference to FIGS. 2A-C. However, when testing receiver 214 signal tester 106 compares signal 138 with a test signal 238, wherein receiver 214 may be adjusted via adjusting signal 242. Further, when testing transmitter 220, signal tester 106 compares signal 240 with test signal 136, wherein transmitter 220 may be adjusted via adjusting signal 244.
Now that transmitter 220 and all receivers within receiver array 204 have been tested, the remaining transmitters within transmitter array 206 and the same receivers within receiver array 204 additionally need to be tested. For example, FIG. 2E shows transmitter 218 and receiver 208 being tested at a time t5.
In operation, first of all, receiver 208 must be again connected to communication channels 112 and 114. Further, transmitter 220 must be disconnected to communication channels 116 and 118. Then transmitter 218 is connected to communication channels 116 and 118.
The testing is similar to that discussed above with reference to FIG. 2A. However, when testing transmitter 208 signal tester 106 compares signal 138 with a test signal 246, wherein receiver 208 may be adjusted via adjusting signal 250. Further, when testing transmitter 218, signal tester 106 compares signal 248 with test signal 136, wherein transmitter 218 may be adjusted via adjusting signal 252.
The remaining receivers within receiver array 204 and transmitter 218 are then tested, commensurate with the multiple connecting/disconnecting when required. Then transmitter 216 and the same receivers within receiver array 204 are then tested in a similar manner.
Transceiver 200 can also be tested in a loop back method. Again however, inherent problems with a loop back test as discussed above with reference to transceiver 100 would be present in the test of transceiver 200 also. Further, the multiple connection/disconnections would still need to be performed to test all transmitters and receivers in transceiver 200.
Accordingly, for at least the foregoing reasons there exists a need for a system and method to efficiently and accurately test a transceiver having a transmitter array and receiver array.